.container {
   display: grid;
   grid-template-columns: 40px [line2] 50px auto [line4] 50px 40px;
   grid-template-rows: [row1-start] 35px 50px 30px;

   border:1px solid #ddd;
   margin-top:10px;
}

.child {
  padding: 5px;
  background: #d4e6f1;
  margin: 5px;
}

.child-1 {
  background: lightblue;
  grid-column : line2 / line4;
  grid-row : row1-start / 3;
 }


 .child-2 {
   background: lightgreen;
   grid-column : 1 / span 2;
   grid-row : 2 / 4;
  }